Rotary kiln



June 2o, 1933. E RZNNE 1,914,462

ROTARY KILN Filed July 9, 1951 INVENTOR.

Patented June 2Q, i933 UNETD STATES PATENT QFFlQ.

EINAR RQNNE, OF COPENHAGEN, DENMARK, ASSIGNOR TO F. Il. SMITH c CO., 0FNEW' YORK, N. Y., A CORPORATON OF NEW JERSEY ROTARY `KILN Applicationled .Tuly 9, 1931, Serial No. 549,610, and in Great Britain August 25,1930.

This invention relates to the burning in a rotary kiln of a materialwhich is delivered to the kiln in the form of a slurry, such as rawslurry for the manufacture of hydraulic cement.

Economy in the operation of rotary kilns has been accomplishedheretofore by the suspension within the drying Zone of the kiln ofmovable heat transmitting bodies, such as chains, rings, network or thelike, the transmission of heat from the combustion gasesto the materialto be burned being increased by these bodies. The provision of heattransmitting bodies in the drying Zone of a rotary kiln, however, in theburning of some kinds of materials, creates so much resistance to thepassage of the material through the kiln tube as to reduce the output ofthe kiln.

It is the object of the present invention to overcome this disadvantageand to increase the effectiveness of the heat transmitting bodies.

In accordance with the invention, the kiln y is made up of two or moreindependently rotating tube sections and the drying is carried outwholly or partly in one of the sections which is furnished with heattransmitting bodies, such as chains, rings, network or the like, andwhich is rotated at a higher speed than the other tube section or tubesin which the burning is carried out. In this manner the slurry-likematerial, which covers the surface of the heat transmitting bodies inthe form of a iilm, is brought into more intimate contact with thecombustion gases from the burning Zone and the transmission of heat isthereby increased. The rate of movement of the material through thedrying zone is also increased and a higher output is secured.

rlhe section which forms the burning zone and the independently rotatingsection which forms the drying Zone may be arr ranged in alignment, oneafter the other, but

the inclination oi the axes of the tubes, as will be understood, may bevaried according to the speed at which the material is to pass throughthe two parts or the kiln. The drying section may also be arrangedotherwise with respect to the burning section with suitable provisionfor the conduction of the material and of the combustion gases from oneto the other.

The slurry-like material may be intro- 55 duced into the drying sectionin any usual or suitable manner and the drying .section may have suchshape and dimensions as will be best suited to the conditions ofoperation.

In the accompanying drawing, in which a o convenient embodiment of theinvention is illustrated,

Figure l is a diagrammatic view, partly in elevation and partly insection, and

Figure 2 is a detail view in longitudinal 65 section showingparticularly the connection between the two parts of the kiln.

rlhe kiln shown comprises a part or section l which forms the burning`Zone and a part or section 2 which forms the drying zone, the twosections being mounted in alignment with each other but arranged torotate independently of one another. ylhe drying acne is provided withheat transmitting bodies in the iorm of chains 3 and for the purpose or'providing room for a large number oi' such chains and for the passage ofa large amount of material the upper part of this section is enlargedrelatively to the rest of so the section. The gases of combustion aredrawn out through a smoke chamber L and the slurry is introduced throughan inlet pipe 5.

The connection between the two sections 85 l and is preferably as shownin detail iii Figure 2. The lower end of the drying section 2 extendstelescopicallv into the upper end of the burning section l. 'the latterbeing provided with helical ribs 6 and an internal 90 flange 7 toprevent any material passing backward. The joint between the twosections l and 2 is surrounded by a casing 8 which is fixed to the lowersection l to rotate therewith but can move relatively to the upper 95section 2. This casing is sealed with respect @a Upper section 2 by anannular plate l0 i h slips a grooved membern li any material passes backfrom the section l througf. the joint, it is caught by the casingl 8 andis returned into the section l by pipes 9 which run partly around thekiln in a direction opposite to that of the rotation of the kiln.

The section 1 may berotated as usual, as by a gear ringr 12 and gear 13.and the Section 2 may be rotated similarly, but at a higher speed. as bya gear ring 14 and gear 15.

I claim as mv invention:

l. A rotary cement burning kiln comprisinnr independently rotatablesections in alignment and forming respectively a drying zone and aburning zone, means to rotate said sections independently of each other,a casing surrounding the joint between the sections, the casing beingfixed to one of the sections and movable with respect to the othersection, means to form a slip seal between the casing and said othersection, and means to transfer material from the casing to the burningzone.

2. A rotary cement burning kiln comprising independently rotatablesections in alignment and forming respectively a drying zone and aburning zone, means to rotate said lsections independently of eachother, a easing surrounding the joint between the sections, and a pipeconnected at one end with the ch amber of the easing and at the otherend into the burningr zone, such pipe extending around the kiln in adirection Opposite to that of the rotation of the kiln.

This specification signed this 22nd day of June, A. D. 1931.

EINAR RQNNE,

CERTIFICATE OF CQRRECTIN.

Patent Ne. 1,914,462. June 20, 1933.

ElNAR RONNE.

li is hereby certified tha the name of he assignee in ile above numberedpaient was erroneously described and specified as "i". L. Smith & C0."whereas said neme should have been described and specified as "F, L.Smidth & C0." as shown by the records of assignments in this eiiiee; andthat the said Letters Patent should be read with this correction thereinthat the same may conform o ihe record of the case in the Pateniv fice.

Signed end'sealed this 29th day of August, A. I). i933.

lili. l, Meere.

(Seal) Acting Commissioner of Patentev

